Concrete mixer with two compartment drum



Nov. 8, 1938. J. P. FA BER CONCRETE IIXER WITH TWb CQMPARTMENT DRUM 2Sheets-Sheet 1 Filed Nov. 9, 1 935 INVENTOR. at-(4,

' ATTORNEY.

Nov. 8, 1938; v J.- P. FABER CONCRETE MIXER WITH TWO COMPARTMENT DRUM 2Sheets-Sheet 2 Filed Nov. 9, 1935 l mhll.

" ATTORNEY.

Patented Nov. 8, 1938 CONCRETE MENT John P. Faber, 'nunenen, N. J., someConcrete Machinery field, N. J., a corporati Application November 9,

4 Claims. '(Cl. 259-164) The present improvements relate in general toconcrete mixers and more particularly to that type of mixer wherein theingredients of the batch are mixed in two compartments of a sin- 5 gledrum, and are in the nature'of an improvement in the co-pendingapplication of James E. Bushnell and John P. Faber, Serial No. 632,878,filed September 13, 1932,

In former practice, the batch of ingredients for the mixing and placingof concrete comprising among others, sand, cement, crushed stone gravel,water, etc., was mixed in a drum for a prescribed interval and thereupondischarged. Such a structure imposes limitations on the capacity of themixer. It is therefore an object of the present improvements to providean improved single drum unit which increases the output of batches abovesixty percent and improves the quality of the mix".

It is a further object of the present improvements to provide improvedmeans and methods of charging, mixing and batch into and out of each ofa plurality of mixing compartments in a single drum.

Novel means and methods are furthermore provided for charging, mixing,and discharging a concrete batch into and out of each of a plurality ofmixing compartments in a single drum, while maintaining the rotarymixing movement of the ingredients. Accordingly, the improvementsprovide for the rotary mixing of the aggregate, water, etc., from themoment the first ingredients enter the first compartment, thence withoutinterruption until the last compartment is discharged. The rotary mixingis therefore not interrupted but actually continues during transfer ofthe batch from one compartment to an- .other. g

A further object is to provide a novel type of mixing drum, having aplurality of compartments, whereby a batch may be mixed for part time ineach compartment, so that while one batch is receiving its final partialmixing in the last compartment, another complete batch may besimultaneously receiving its initial partial mixing in the firstcompartment. v

Another object is to provide an improved type of mechanism fortransferring the partially mixed batch from one compartment to another,as well as an improved means for preventing transfer between suchcompartments. A further object is to provide novel mixing blades fortransferring the batch from one compartment to another as well as anovel door or battle for preventing transsingle compartment discharginga concrete MIXER wrrn 'rwo coMrARn DRUM assignor to Ban- Company,Plainon of New Jersey 1935, Serial No. 49,022

fer, but likewise functioning in the operation cycle when open orclosed.

An additional object is to provide an improved mechanism foraccomplishing a continuous cycle of operation, including charging,mixing, transferring, mixingagain and discharging a succession ofbatches in a series of compartments in a single drum unit.

' Another object is to provide a novel reinforcement means for theblades, and also to provide a novel support for the closure or baffle.

A further object is to provide novel means and methods for operating adouble-compartment drum.

Other objects include improvements in details of construction ofdouble-compartment drums and in methods of their operation. Furtheradvantages-and objects of the improvements will be apparent to thoseskilled in the art upon reference to the accompanying specification anddrawings, in which-- Fig. ,1 is a longitudinal section through the mixerillustrating one embodiment of the improvements;

Fig. 2 is a section on line 2-4 of Fig. 1;

Fig. 3 is a section on line 3-3 of Fig. 1;

Fig. 4 is a section on line 4-4 of Fig. 1;

Fig. 5 is a diagrammatic showing of a modification, in plan view.

Referring to the drawings, the single rotary mixing drum 5 is providedwith bearing bands or rings 6 upon which the drum revolves, beingsupported on a set of four bearings or supporting rollers (not shown).The drum is driven by a suitable power unit (not shown) through gearingin mesh with ring gear 1, fixed about the circumference of the drum, allas is common in the art.

The drum is equipped with the usual charging inlet 8, discharging outlet9 and a transverse partition l which divides the drum into two mixingcompartments H and I2. An opening I4 is provided in partition H] foraffording communication between the two compartments.

As illustrated the first compartment H may be provided with a series ofmixing blades l and a series of mixing and transferring blades l6, whilethe second compartment isprovided with a series of mixing blades l1. Anysuitable charging means for the drum may be employed.

' In the illustrated embodiment the usual pivoted skip I8 is providedfor introducing the dry aggregates, such as sand, cement, crushed stoneand the like, into the first compartment II. A

ter with the aforementioned batch.

' in the bafiie or closure 20. As illustrated, this element ispreferably in the form of a slidable door which may be reciprocatedlongitudinally of the drum. It is obvious that such a door may be madetoslide across the opening I4, in a plane parallel to partition I0, ifdesired, without departing from the improvements.

The door 20 is preferably carried on an actuating rod 2| which extendsto the exterior of the drum where it is operatively connected by levers22 and rods 23 to a power discharge mechanism 24 of a type, such as thatset forth in the patent to Shafer 1,415,411 of May 9, 1922. In' thismanner the door 20 may be advanced and retracted from full to dottedline position and return, as desired, for opening or closing the openingI4. The transfer of the batch from compartment II to compartment I2 maythus be permitted or prevented.

A reinforcement in the form of a collar 25 is flanged and secured to theadjacent tips of transfer blades I6 (see Figs. 1 and 2). This elementserves to reinforce and support the tips or free edges of the transferblades which are adjacent the axis of the drum where they direct thebatch through opening I4. Part of the most severe burden inflicted onblades I6, is imposed on them at this region, and the provision of thereinforcement 25 therefore affords a more rugged and durableconstruction. The vitality and efiiciency of the unit as a whole, isgreatly increased.

In order to facilitate the operation, the door 20 is partially supportedon collar 25 and bearing 26 by means of rod 2I.

on rod 2| so that the closure may rotate with the may be described asfollows:

With the drum 5 rotating with the parts in full line position in Fig. 1,compartment II is-empty and chute I9 is in the position for dischargingand emptying compartment I2. Upon pulling handle 5|, whereby the skip I8is charged into the mixing blades I5 of The batch is mixed in therotatmg compartment II by the combined action of blades I5 and I6. Theformer mix the batch and advance it toward the central region of thecompartment and blades I6 pick it up there and further mix and advancethe batch toward outlet 2,136,045 conduit 29 is usually provided forsupplying wai The drum is discharged by means of the chute,

I4. As shown by the arrow, the batch impinges the baflle or closure 20and is returned to the compartment II for further'mixing. The elements I5, I6 and 20 therefore give the batch a thorough mix by transferring itback and forth during the mixing operation,

When the batch has been given the predetermined partial mixing which itis to receive in compartment I I, the batch meter or timer 50 releasesthe mechanism which automatically operates and withdraws chute I9 fromfull to dotted line (closed) position. Thereupon mechanism is releasedwhich automatically operates member 24 for retracting closure 20 fromfull to dotted line (open) position. The drum 5 is rotating and thebatch in I I is being mixed therein, and the blades I6, while turningand mixing, direct and transfer the batch through opening I4 into theregion of the rotating blades I! in compartment I2. Without interruptionin the mixing of the batch, the blades I! pick up the batch and itthereupon is mixed by them in compartment I2.

The power discharge mechanism 24 thereupon retracts door 20 to closedposition and then skip I8 feeds a new batch into compartment II. Thisnew batch is given its initial partial mixing in compartment II, andconcurrently, the first batch is receiving its final partial mixing incompartment I2. The blades I! mix the batch and advance it toward themiddle and end of the compartment. When the prescribed partial mixi iscompleted in compartment I2, the batch has been mixed for the fullmixing interval required by building or highway specifications. Thebatch has received a half mix" in each compartment, the total of whichis the mix in a single compartment drum.

At this stage, the drum carries one completely mixed batch incompartment I 2, and one partially mixed batch in compartment II. Thepower discharge mechanism (not shown) now swings chute I9 intodischarging position (full line) whereupon batch #1 is dischargedentirely from the drum. By the time this operation is cqmpleted, thepartial mixing of batch #2 is accomplished in compartment I I, so thatthe door 20 is opened and chute I9 withdrawn, whereupon batch #2 istransferred into compartment I 2.

It is therefore seen that the operators attendbatch #1 is completed (theproper interval hav-' ing lapsed) the batch meter unlocks or releasesthe power discharge mechanisms and the operator may then cause the chuteI9 to be swung out of compartment I2, and cause the door 20 to move intosaid compartment for uncovering opening M. The parts are now inbatch-transferring position and blades I6 transfer the batch into theregion of mixing blades I! in compartment I 2. The door 20 may bethereupon closed and the operator may again actuate the mechanism forequivalent of one full erator may 'elevate be omitted if desired. Inpreferred embodiments, a disheddoor with a single sealing flange, as

elevating the skip with another batch, and for discharging compartmentII by swinging chute [9 into same.

It may be found preferable to employ two batch meters, one with eachpower discharge mechanism. In such an arrangement, the opthe skip forcharging compartment ll, whereupon the batch meter is set so as to lockclosure for the prescribed mixing interval for compartment H, uponcompletion of which the power discharge mechanism controlling theclosure is released and the operator may for example, like a single drummixer..

'ample, the door 20' may actuate a lever for'retracting the closure. Thedischarge chute I9 is similarly locked by a second batch meter whichupon completion of the mixing interval in compartment l2, releases the-power discharge mechanism whereupon the optransferred and mixed in thesecond. The chute compartment I I .in the mixing operation along withthe blades in tageous since it secures i9 may' then be operated fordischarging the completely mixed batch. 0n the other hand, -a differentoperation may be followed wherein the chute l9 may be kept indischarging position, and a full mixing of the batch may be accomplishedin compartment H with door 2!! closed. The door may then be opened fortransferring the batch to compartment l2 whence it is discharged as soonas blades l'l advance it to the chute 19.

g It is significant that the blades in the first compartment act asmixing and transfer blades and direct the aggregates toward anddownwardly into the blades in the second compartment so that even thoughpartial mixing is accomplished in isolated compartments, the mixing goeson uninterruptedly before, during and after transfer. The character ofthe mixing operation in may be different fromlthat in compartment 12,due to the difference of movement of the materials in each compartment.Furthermore, the participation of the door 20 the center of the druminsures better and quicker mixing, "and the presence of the doorcontributes to the improved quality of the batch.

The reinforcing collar is particularly advan the tips of themixingtransfer blades l6 together, and through .the rod II and door 20,the partition I0 and blades l6 are braced and reinforced one by theother.

In providing the battle or closure 20 the separation of the aggregatesentering compartment I2 is prevented by breaking their fall. It also mayretard the movement of aggregates fromthe door to the discharge chute.The closure 20 thus permits the simultaneous movement of the dischargechute to closed position and the closure to open or' transferringposition without danger of premature discharge of any portion of thepartly mixed batch entering the second compartment from the first, andenables the opera.-

.tor to increase the speed of the operation. A

skirt 5 maybe provided on the sealing flange of closure 20, forprotecting the opening, but may i a discharge means and a connectingdevice whereby said member 8. In a single seen in outline in Fig. 5, isemployed.

A slightly modified form is diagrammatically supported by collar extendsthrough the housing M. the entire drum and extends from actuating clo-22 The housing 2| the whole is partially 25. A bifurcated support illand through either end thereof where it is fixedly supported on themixer frame. The support 10 insures alignment of the door and opening,of sagging of the I claim: 1. A single drum transverse partition and asecond compartment and prevents any possibility door or its actuatingmeans.

concrete mixing machine, a defining a first compartment for partiallymixing batches of concrete in each, said partition having 20 a dischargeopening, mixing blades in each of said compartments, compartment cement,a movable opening, discharging blades for impelling the parthrough theopening obstructed tially mixed batch means for charging said first withwater, sand, dry aggregate and door normally closing said by said door,a member operable from the exterior of said drum for opening said doorand moving it into said second compartment whereby the partially mixeddoor are supported batch may for said second, compartment,

be transferred and and by said, discharging blades said device alsoforming a connection between said blades.

2. A single drum transverse partition concrete mixing machine, adefining a first compartment and a second compartment for partiallymixing batches of concrete in each, said partition having a dischargeopening,

said compartments, compartment with and cement, a reciprocatingdischarging said opening, the partially mixed obstructed by said door,

bearing and connecting said blades, a

mixing blades in each of means for charging said first water, sand, dryaggregate door normally closing blades'for impelling batch through theopening a bearing supported by joined to said member supported by saidbearing and operable from the exterior of the drum said door whereby thepartially for supporting and opening mixed batch may be transferred tosaid second compartment, and a discharge means for having a transversesaid second compartment.

drum concrete mixing machine partition defining two commixing batches ofconcrete and a discharge opening in said partition through which saidpartially mixed batches are transferred from one compartment to theother,

the combination of both compartments, tially mixed batch from thecompartment and for separating the for mixing batches in transferring aparfirst to the second batches in means means for the two compartmentsduring non-transferring periods, means extending to the exterior of the.drum and connected means in the separating moving the saidmeans withsaid transferring and interior of the drum for and a bearing support forsaid moving means mounted in one of said compartments and connected withand rigidly connecting certain elements of said mixing means, to

form therewith a unitary structure.

4. In a single drum concrete having a transverse partments for part1mixing machine partition defining two comally mixing batches of con,

crete and a discharge opening in said partition through which saidpartially mixed batchesare transferred from one compartment to theother, the combination-of means for mixing batches in both compartments,means for transferring a partially mixed batch from the first to thesecond compartment and for separating the batches in the twocompartments during non-transferring means extending to the exterior ofthe 10 drum and'connected with said transferring and periods,

separating means in the interior of the drum for moving thesaid meansand a bearing support for said moving means mounted in one of saidcompartments and connected with and rigidly connecting certain elementsof said mixing means, to form therewith a unitary structure, saidstructure also supporting said transferring and separating means.

JOHN P. FABER.

